A psychologist has developed a mental alertness test. She wishes to study the effects (if any) of type of food consumed on mental alertness. Twenty-one volunteers were randomly divided into two groups. Both groups were told to eat the amount they usually eat for lunch at noon. At 2:00 P.M., all subjects were given the alertness test. Group A had a low-fat lunch with no red meat, lots of vegetables, carbohydrates, and fiber. Group B had a high-fat lunch with red meat, vegetable oils, and low fiber. The only drink for both groups was water. The test scores are shown below. Group A 67 93 82 69 76 47 43 58 92 63 52   Group B 70 57 75 59 66 49 55 46 45 91 89 72 Use a 10% level of significance to test the claim that there is no difference in mental alertness distributions based on type of lunch. (a) What is the level of significance? (b) Compute the sample test statistic. (Use 2 decimal places.) (c) Find the P-value of the sample test statistic. (Use 4 decimal places.)

A company wishes to evaluate the effect of package design on one of its products, a certain brand of cereal. The four package designs are to be tested in different stores throughout a large city. There are 20 stores available for the study. The amount of cereal sold is known to vary depending on the size of the stores. The 20 stores are divided into five groups of four stores each by size. The following sales figures ($1000s) were obtained after a 1-month period. Stores Design A Design B Design C Design D 1 40 33 37 38 2 45 27 32 40 3 43 31 30 41 4 44 38 40 42 5 56 45 49 42 Enter the above data into a suitable software and then conduct an analysis of variance without blocking to test whether there is evidence of a significant difference in mean sales of different package designs. Use alpha=0.01. What is the conclusion for the null hypothesis that all treatment means are equal? O Do not reject HO. There is sufficient evidence to conclude that the average sales for all stores are not…

A company wishes to evaluate the effect of package design on one of its products, a certain brand of cereal. The four package designs are to be tested in different stores throughout a large city. There are 20 stores available for the study. The amount of cereal sold is known to vary depending on the size of the stores. The 20 stores are divided into five groups of four stores each by size. The following sales figures ($1000s) were obtained after a 1-month period. Stores Design A Design B Design C Design D 1 40 33 37 38 2 45 27 32 40 3 43 31 30 41 4 44 38 40 42 5 56 45 49 42 Enter the above data into a suitable software and then conduct an analysis of variance with blocking (analyze this data as a complete block design) to test further whether there is evidence of a significant difference in mean sales of different package designs. Use alpha=0.01. What are the sums of squares for Blocks? Provide your answer to the nearest 2 decimal places.

Dr. Slim developed a new drug he hypothesizes will cause people to lose weight. He randomly assigned participants into either the control group (no drug) or the experimental group (1 pill a day for two months). At the end of the 2ndmonth he weighed each participant and recorded the amount of weight loss (i.e., measured in pounds) since the beginning of the program. The results were as follows: control group experimental group 21 33 20 17 26 39 27 22 21 17 24 19 17 32 13 29 88 19 32 31 29 31 26 30 29 36 22 26 Analyze the data using an independent two sample t-test and interpret the results.

Do people feel hungrier after sampling a healthy food? The authors of a consumer research paper carried out a study to answer this question. They randomly assigned volunteers into one of three groups. The people in the first group were asked to taste a snack that was described as a new health bar containing high levels of protein, vitamins, and fiber. The people in the second group were asked to taste the same snack but were told it was a tasty chocolate bar with a raspberry center. After tasting the snack, participants were asked to rate their hunger level on a scale from 1 (not at all hungry) to 7 (very hungry). The people in the third group were asked to rate their hunger but were not given a snack. The data in the table are consistent with summary quantities given in the paper (although the sample sizes in the actual study were larger). TreatmentGroup Hunger Rating SampleMean SampleStandardDeviation Healthy 5 8 7 4 7 3 4 7 6 5.6667 1.7321 Tasty 4 1 5 2 6 2 5 3 4 3.5556…

A clinical psychologist wants to test the effectiveness of three new therapies that have been developed for reducing anxiety symptoms. The researcher recruits 15 participants and randomly assigns them to take part in Therapy A, Therapy B, or Therapy C for a month. At the end of the month, the researcher measures the participants' anxiety symptoms on a scale from 1 to 10 (where a higher score means more anxiety symptoms). The participants' scores are shown below: What is the appropriate test to use ? 3. What are the null and alternative hypotheses ? 4. Using a two-tailed alpha of .05, determine what the critical value is 5. Calculate the test statistic 6. State whether you reject or fail to reject the null hypothesis for the omnibus test 7. Calculate and report the effect size for the omnibus test 8. Perform a Post-Hoc Test. Report the significance of each pairwise comparison

A randomly sampled group of patients at a major U.S. regional hospital became part of a nutrition study on dietary habits. Part of the study consisted of a 50-question survey asking about types of foods consumed. Each question was scored on a scale from one (most unhealthy behavior) to five (most healthy behavior). The answers were summed and averaged. The population of interest is the patients at the regional hospital. The current survey was implemented after patients were subjected to this education, and it produced the following sample statistics for 25 patients sampled:  and s = 1.02. We would like to know if the education improved nutrition behavior. We test the hypotheses H 0:  = 2.9 versus Ha:  > 2.9. The value of the t test is 1.96, and:   a. P-value > 0.1.   b. 0.025  P-value < 0.05.   c. 0.25  P-value < 0.01.   d. 0.05  P-value < 0.1.   Given the least squares regression line y = 3 x – 3, which of the following is true?   a. The…

A research article describes a study that investigated the relationship between depression and chocolate consumption. Participants in the study were 931 adults who were not currently taking medication for depression. These participants were screened for depression using a widely used screening test. The participants were then divided into two samples based on their test score. One sample consisted of people who screened positive for depression, and the other sample consisted of people who did not screen positive for depression. Each of the study participants also completed a food frequency survey. The researchers believed that the two samples were representative of the two populations of interest—adults who would screen positive for depression and adults who would not screen positive. The paper reported that the mean number of servings per month of chocolate for the sample of people that screened positive for depression was 8.37, and the sample standard deviation was 14.85. For the…

To perform a certain type of blood analysis, lab technicians must perform two procedures.The first procedure requires either one or two separate steps, and the second procedurerequires either one, two, or three steps.a. List the experimental outcomes associated with performing the blood analysis.

A recent study investigated whether cell phone users experience separation anxiety when they cannot access their phones. Because blood pressure increases with anxiety, the researchers used systolic blood pressure as an operational measure of anxiety. The experiment involved a random sample of cell phone users that were divided into two groups at random. One group of participants completed a survey while their phones were locked in a cabinet in a separate room and the other group of participants completed the same survey while their phones were nearby. (The survey questions were unrelated to cell phone use.) At the end of the survey, theresearchers measured each participant's systolic blood pressure. The same experiment was conducted in Montreal, Toronto, Vancouver, and St. Zotique. The blood pressure data needed is below. Use these data to answer the following question: compute r2 for the data collected in st. zotique. Please answer to 5 decimal places. Cell Phone (CP) No Cell Phone…